In a metalized film capacitor in the prior art, a metalized film is used in which a metallikon-vicinity vapor-deposited electrode 2 on a polypropylene film 1 illustrated in FIG. 1 is thickly formed and a non-metallikon-vicinity vapor-deposited electrode 3 thereon is thinly formed by vapor deposition, and an insulating margin 4 is formed at an end region of the film opposed to the metallikon. When the polypropylene film undergoes dielectric breakdown in this metalized film capacitor, the vapor-deposited electrode around the dielectric broken site is scattered by discharge energy therefrom, whereby the capacitor has a self-restoring function of restoring electric insulation of the dielectric broken site. However, at a high temperature and a high pressure, the number of dielectric broken sites increases so that the self-restoring function is not sufficiently obtained. Thus, the capacitor may turn into a short circuit mode. As illustrated in, for example, FIG. 11, in a metalized film capacitor obtained by stacking or winding metalized films each having an vapor-deposited metal film on a dielectric body (plastic film), the dielectric may be broken at a site marked “x” in the drawing. When the capacitor has insufficient self-healing performance (scattering performance of the vapor-deposited metal), the broken film becomes electrically conductive to the vapor-deposited metal on the other metalized film, which is arranged beneath this metalized film, through the broken dielectric portion.
A smoothing capacitor of an inverter circuit is used at a high temperature and a high voltage, and is further intensely required to have safety. Thus, a metalized film in which an vapor-deposited electrode is divided into plural segments is adopted (see, for example, Patent Documents 1 to 3). Examples of a metalized film in which such split electrodes are formed are illustrated in [FIG. 2-A] to [FIG. 2-C].
In [FIG. 2-A], an insulating margin 12 is formed at an end region of a metalized film that is opposed, in the width direction thereof, to a metallikon-connection section 10 of the film. By width direction insulating slits 5 and longitudinal direction insulating slits 6, split electrodes 7 are formed. These split electrodes 7 are connected to each other through fuses 8 in each row of the electrodes 7. Furthermore, at the vapor-deposited electrode in the vicinity of the metallikon, the metallikon-connection section 10 is separated from some of the split electrodes 7 by longitudinal direction insulating slits 9. The metallikon-connection section 10 is connected to each of the split electrodes 7 through a fuse 11.
In [FIG. 2-B], an insulating margin 12a is formed at an end region of a metalized film that is opposed, in the width direction thereof, to a metallikon-connection section 10a of the film. Honeycombed split electrodes 7a are formed by Y-shaped insulating slits 13a. These split electrodes 7a are connected to each other into the form of arranged rows through fuses 8a. 
In [FIG. 2-C], an insulating margin 12b is formed at an end region of a metalized film that is opposed, in the width direction thereof, to a metallikon-connection section 10b of the film. Honeycombed split electrodes 7b are formed by Muller-Lyer-shaped insulating slits 14a. These split electrodes 7b are connected to each other into the form of arranged rows through fuses 8b. 
When dielectric breakdown is generated in the dielectric body of a metalized film capacitor using such a metalized film having split electrodes, the capacitor has the above-mentioned self-restoring function. Simultaneously, the capacitor has the following functions to keep high safety certainly: even when dielectric breakdown is generated beyond the self-restoring function of the metalized film capacitor, an electric current flows into the split electrodes in which the dielectric breakdown is generated from the split electrodes around the electrodes; thus, the vapor-deposited electrode of the concerned fuse regions is scattered, whereby the dielectric-breakdown-generated split electrodes are separated from the other split electrodes so that electric insulation is restored.
Furthermore, when the area of the split electrodes is made small, a decrease in the capacity based on the action of the fuses can be restrained so that the lifespan of the capacitor can be made long. However, when the split electrodes are made too fine, the energy of the split electrodes becomes small. Thus, when the split electrodes undergo dielectric breakdown, the fuses come not to act easily so that the safety of the capacitor declines. This phenomenon becomes more remarkable as the temperature becomes high.
When the split electrode area is made small, the number of fuses increases. However, the fuses have a higher resistance than the split electrodes. It is therefore reported that heat generated from the capacitor increases (see, for example, Patent Document 4). Such an increase in self-heating causes a fall in the voltage endurance performance or safety-keeping performance. The temperature of the capacitor element is most highly raised, in particular, at the center by self-heating, so that the center becomes poorer in voltage endurance performance or safety-keeping performance than the other regions.
Thus, in order to overcome the above-mentioned inconvenience, the following means has been invented: a means in which split electrodes, as well as a non-split electrode large in area (non-split electrode section), are collectively arranged (see, for example, Patent Document 5). In a metalized film capacitor described in Patent Document 5, split electrodes divided from each other by slits are arranged at the insulating margin side, and a non-split electrode section is arranged at the terminal-connection section side (metallikon-connection section side) thereof. The split electrodes are formed to have a structure in which the area of the vapor-deposited electrodes becomes small at positions nearer to the insulating margin.